21494919 has 8 divisors (see below), whose sum is σ = 30345840. Its totient is φ = 13486976.

The previous prime is 21494917. The next prime is 21494929. The reversal of 21494919 is 91949412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21494919 - 2¹ = 21494917 is a prime.

It is a super-2 number, since 2×21494919² = 924063085633122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21494911) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 210684 + ... + 210785.

It is an arithmetic number, because the mean of its divisors is an integer number (3793230).

Almost surely, 2^21494919 is an apocalyptic number.

21494919 is a deficient number, since it is larger than the sum of its proper divisors (8850921).

21494919 is a wasteful number, since it uses less digits than its factorization.

21494919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 421489.

The product of its digits is 23328, while the sum is 39.

The square root of 21494919 is about 4636.2613170528. The cubic root of 21494919 is about 278.0429819848.

The spelling of 21494919 in words is "twenty-one million, four hundred ninety-four thousand, nine hundred nineteen".